Why does my reservoir cap keep coming off?
it really just sounds like your coolant level is low. Since the coolant level is low, you have a decent amount of air pressure building up under the radiator cap. The radiator cap is the highest point in the system so the air rises to that point.
What happens when the coolant stops in an expansion tank?
At that point, the coolant flow will stop, making the expansion tank a closed system. This system will have no way to vent is pressure, about that of the radiator pressure cap rating, until the expansion tank pressure cap is removed. This can cause some problems with the expansion tank.
Where does the coolant go in an overflow tank?
With this form of system, as the system pressure is increased, excess coolant is forced out the radiator vent and into the expansion tank. As system pressure drops, cooling is drawn from the expansion tank and into the radiator and engine.
Where is the cap on an expansion tank?
In fact, the radiator is lacking any sort of cap or fill neck in most cases since you fill coolant from the tank. Cooling systems that use expansion tanks will have the pressurized radiator cap located on the expansion tank rather than the radiator. (Image/Mishimoto)
Why do you need an expansion tank for a radiator?
It prevents a slightly overfilled radiator system from venting onto the ground. The use of an expansion tank, with a conventional radiator, adds a very small amount of additional coolant to the system.
Where does the coolant go in an expansion tank?
The cooling system is constantly under pressure with the use of an expansion tank. Instead of sending the expanding coolant to the tank once it reaches a certain pressure, the coolant is always cycled through the radiator and out to the expansion tank.
What happens when the coolant tank overflows?
If there is a leak in the expansion tank, or if the cap is not screwed on tightly, once coolant temperature exceeds its boiling point at normal atmospheric pressure, any coolant entering the expansion tank via the overflow valve will immediately boil – some will be vaporized immediately and some will be forced out as liquid.
What happens if you remove the cap on a coolant tank?
And people have been severely burned who did not know about this hazard and removed the cap too quickly when the system was under pressure. Think of a stew pot with a lid on it – with the lid on, it is merely simmering, take off the lid and a few minutes later it will be boiling over.
Can a bad radiator cap cause the overflow tank to collapse?
While you’re in there, check to make sure your coolant overflow tank is working properly. You may have a bad radiator cap if the radiator hose collapses. The vacuum won’t be released by the radiator cap properly and it will cause the radiator hose to collapse during the cooling down period.